Response to Jerry Coyne's Review of Icons of Evolution

On April 12, 2001, Nature published a review of Jonathan Wells's book, Icons of Evolution, by University of Chicago evolutionary biologist Jerry A. Coyne. (Nature 410, 745-746). About half of Coyne's review consists of personal attacks on Wells, while most of the other half took exception with Wells's criticism of the way Darwinists use distorted drawings of vertebrate embryos to support their theory. Wells then wrote a letter to the editor of Nature to point out factual errors in Coyne's review. The editor refused to print the letter.

What follows is Wells' original letter to the editor of Nature.

April 16, 2001

To the Editor of Nature:

Jerry Coyne's review of my book, Icons of Evolution (NATURE 410: 745-746, 12 April 2001), includes many personal attacks on me, but his only substantial criticism is that I am mistaken in faulting Darwinists for distorting early vertebrate development to fit their theory. According to Mr. Coyne, vertebrate embryos "provide strong evidence for common ancestry and evolution. Embryos of different vertebrates tend to resemble one another in early stages, but diverge as development proceeds."

This claim is false. The various classes of vertebrates follow a "developmental hourglass" pattern as they progress from egg to adult. The wide top of the hourglass represents the large differences that are present in early development, the narrow neck represents a partial convergence midway through development, and the wide bottom represents the major differences seen in adults. This pattern is well documented in the biological literature. (1)

Mr. Coyne actually concedes this point later in his review, agreeing with me that "the earliest vertebrate embryos (mere balls of cells) are often less similar to one another than they are at subsequent stages." How can vertebrate embryos both "resemble one another in early stages" AND be "less similar to one another than they are at subsequent stages"?

According to Mr. Coyne, the differences in early vertebrate embryos are due to "adaptation to widely varying amounts of yolk in their eggs." This may explain why some cleavage planes do not pass all the way through the eggs of reptiles and birds, but it does not explain the radically different rotational cleavage pattern that distinguishes mammals from all other classes. In general, early stages are NOT more similar than later ones. As embryologist William Ballard wrote in 1976, it is "only by semantic tricks and subjective selection of evidence," by "bending the facts of nature," that one can argue that the cleavage and gastrulation stages of vertebrates "are more alike than their adults." (2)

It seems to me that Mr. Coyne's statements are symptomatic of the very problem I criticize in my book: that is, the tendency of some Darwinists to read their theory into, and thereby distort, evidence which doesn't fit it. But the integrity of the scientific enterprise depends on our willingness to question any theory that conflicts with the evidence--even the theory of Darwinian evolution.

Jonathan Wells Discovery Institute, Seattle, Washington, USA

(1) See, for example, Rudolf A. Raff, The Shape of Life (Chicago and London: The University of Chicago Press, 1996), p. 208.